Well, it's unofficially official! A 2009 Mac mini running Snow Leopard with the latest firmware installed supports 8GB of RAM. This would be with the EFI Boot ROM version MM31.0081.B06 (EFI 1.2), which was released back in August. We actually had our friends over at OWC test a Mac mini with 8GB of RAM at that time, but it turns out the test machine was running Leopard. Therefore, the memory wasn't being utilized properly. Here's a part of the message we received from Larry O'Connor today clearing things up.

We have to go back and test again under 10.5.x – see if something else has changed... But, when we tested when you last requested – we had 10.5.x installed with latest firmware and all the latest updates to that point and more than 4GB definitely did not work correctly. Saw the memory, but experienced significant slow down as soon as more than 4.0GB was in physical use.

We just tested the two old models from March 2.0GHz and 2.26GHZ + the current October shipping 2.26GHz and 2.53GHz models – all with the latest 10.6.x Snow Leopard... And they ALL work 100% with 8GB. FULL utilization, no slow down – performance gained for applications open that can result in more than 4.0GB utilized.

So there you have it folks! I hope that clears up some of the confusion going around. It should also be noted that our friends over at OWC are now offering and supporting 8GB memory kits for the 2009 Mac minis.

So why doesn't Apple mention it can max to 8gb? It may help their sales.

How can they market a US$700 upgrade for a $599 machine? (I think it was $1200 a few months ago.) Take a look at the iMac. The low end one doesn't offer a 16GB option in the online store but can take it according to their own spec sheet.

So why doesn't Apple mention it can max to 8gb? It may help their sales.

How can they market a US$700 upgrade for a $599 machine? (I think it was $1200 a few months ago.) Take a look at the iMac. The low end one doesn't offer a 16GB option in the online store but can take it according to their own spec sheet.

Maybe that's why Apple doesn't advertise it? You are right. Most people who are concerned about cost will not go for it. Since many newer macbook pro's can take 8gb capacity.... maybe the price will drop?

Unless you are multitasking, you would not see the real benefit from 8gb set-up.

Right now, the Mac mini is using 9.5mm drives. You should be able to use one the 12.5mm drives in the top bay of the Mac mini server since the optical is typically 12.7mm. It's the bottom bay in question. From what I've seen, it's probably going to be a snug fit.

640GB are the largest in the 9.5mm form factor though. That would be totally safe.

Right now, the Mac mini is using 9.5mm drives. You should be able to use one the 12.5mm drives in the top bay of the Mac mini server since the optical is typically 12.7mm. It's the bottom bay in question. From what I've seen, it's probably going to be a snug fit.

640GB are the largest in the 9.5mm form factor though. That would be totally safe.

The only problem with one 9.5mm and a 12.5mm setup is if you want to run RAID. Don't you need matching drives for a raid setup?

I love Apple but sometimes they are a trip. 8GB in a 2009 Mac mini you know what 8GB will do for me? A lot! 8GB Price should be dropping soon because of increase demand for upgrading the memory on a New iMacs! I really wasn't going to crack my mini opened but for 8GB why not! _________________24" LED Cinema Display,Mac Mini '09, 2.0GHz,
4GB DDR3, 320GB, FW 800 Two 2TB My Book Studio II, Logitech THX Z-5500 5.1 Surround Sound, Monster Cable Optical; 16GB iPhone